The present invention relates to the art of expanding grids for batteries, and in particular, relates to a cam shaft operated punch press for expanding lead alloy battery grid material.
In the field of expanding battery grid material, it is well known to use either rotary or reciprocating punch presses. Even though rotary punch presses are capable of obtaining greater speeds, the reciprocating punch presses are generally preferred in spite of their relatively lower speed. Generally, a reciprocating punch press comprises a punch platen on which are mounted as many as forty-four dyes which reciprocate with the platen to simultaneously punch and expand forty-four notches in a strip of grid material which is being worked on. At the present time, however, the speed of these processes is limited to approximately 200 strokes per minute. At speeds greater than 200 strokes per minute, the vibration caused by the inertia of the machine becomes so great that higher processing speeds are unattainable.
If it were possible, it would be preferred to expand grid material using machines which were capable of making forty-four slits per stroke at a rate of approximately 600 strokes per minute. The major drawback is that no reciprocating expanded metal punch press is known which is capable of obtaining speeds on this order of magnitude.